Type-writing machine.



No. 781,130. PATENTED JAN. 31, 1905.

W. J. CAMPBELL.

TYPE WRITING MACHINE.

APPLICATION FILED n30.29, 190a.

Witnesses UNITED STATES Patented January 31, 1905.

PATENT OFFICE.

WALTER JEROMEOAMPBELL, OF NASHVILLE, TENNESSEE, ASSIGNOR, BY

DIRECT AND MESNE ASSIGNMENTS, TO THE SMITH PREMIER TYPE- WRITER COMPANY,OF SYRACUSE, NEW YORK, .A "CORPORATION OF NEW YORK.

TYPE-WRITING MACHINE.

SPECIFICATION forming part of Letters Patent No. 781,130, dated anuary31, 1905.

- A pli ation fil d December 29,1903. Serial No. 187,081.

To all whom. it may concern: I

Be it known that I, WALTER JEROME CAMP- BELL, a citizen of the UnitedStates, residing at Nashville, in the county of Davidson and State ofTennessee, have invented anew and useful Type-Writing Machine, of whichthe follow-- ing is a specification.

It is a well-known fact that an ordinary operator upon a type-writingmachine strikes all the keys with substantially the same force, theresult being that the type of the smaller characterssuch as periods,commas,.and the likeoften puncture the paper, indent and in time destroythe surface of the platen, and become flattened and deranged by therepeated heavy impacts.

One of the principal objects of the present invention is to providemeans which will to a very great extent eliminate this objectionableaction and the disastrous results caused by careless or inexperiencedoperators. Moreover, the preferred form of structure is such that itdoes not materially alter the general make-up of the machine and mayeasily be applied to those already built and in use. It has been foundthat another advantage flows from the novel combination hereinafterdescribed and claimed, in that a ligher touch is obtained, so that thestructure may be found useful in connection with all the keys and isthereforenot to be limited to employment only with those Which aflectthe paper and the platen; nor is the invention limited to the exactdetails of construction shown and described, as an inspection of theclaims hereto appended will 'clearly indicate that .manymodificationsmay be made without departing from the spirit or scope ofthe said invention.

In the embodiment illustrated, Figure 1 is a perspective view of atype-operating meohanism of a well-known machine. Fig. 2 is across-sectional view of the same through the V the usual connecting-rod8, having an inter mediate turnbuckle 9. The type-bar 5 carries,

at its free end the usual type-head 10, having on its operative face asuitable type 11. The operating mechanism for the type-bar includes arock-shaft 12, yieldingly held in a predetermined position by a suitablespring 13 and carrying contiguous to its front end a finger 14, to whichthe stem 15 of the key 16 is attached. So far as thus described the wellknown in the art.

A crank arm 17 has at one end an enlarged hub 18, which is looselyjournaled on the shaft 12. The free end of this crank-arm is connectedto the lower end of the rod 8. The

mechanism is hub 18 is provided with an annular slot 19, I

through the rock-shaft 12 and has its .ends 10- cated in the slot 19,said ends thus being located in the path ofmovement of the end Walls 20of the slot and constituting means for limiting the free movement of thehubupon the shaft. A spring 22 is coiled upon the rock-. shaft 12 at oneside of the crank-arm 17, and one end of.this spring is suitablyconnected to the crank-arm, preferably by being bent about the same, asshown at 23. The other end of the springrpasses through an opening 24:,formed in a collar 25, that is fitted upon the shaft 12 and is capableof revolutionthereupon, said collar being ordinarily held againstrelative movement with respect to the shaft by means of a set-screw 26,which is threaded through the collar and bears against the shaft,as'shown in Fig. 3.

It is believed that the operation of the device will be clearlyapparent. -Through the the key and type-head, and, while the type willbe elevated with suflicient force to strike the paper upon the platenand make an impression when the key is suitably depressed, if anabnormal degree of force is exerted upon the key the spring will yieldsufficiently to absorb the same, thereby causing the type-arm to alwaysswing with substantially the same force. The amount of this force may bevaried as desired by adjusting the collar 25 upon the shaft, and this isconsidered to be an important feature of the invention, as the tensionof the spring may be changed as desired and with ease. It will also beobserved that after the type is in engagement with the platen the keycan still be forced downwardly without exerting any strain upon theconnections between the shaft and the type-bar, for the reason that thespring will still yield. On the other hand, the yielding movement islimited by the portion, of the stop-pin 21 that projects beneath thearm, as shown in Fig. 2, so that the return of the type-bar is madepositive, and should the bar become stuck it can, if desired, be forcedupwardly through the same medium, the opposite ends of said pin beingmoved into engagement with the end walls of the slot to force thecrank-arm downwardly.

It will thus be seen that this simple structure can be made to obviatethe objections noted in the preliminary portion of the specification, asthe type can be made to strike the paper on the platen with sufficientforce to obtain a suitable impression without puncturing the paper andwithout regard to the strength of the blow imparted to the key. It willalso be evident that this yielding connection relieves the fingers ofthe shock ordinarily imparted to them in starting the keys in theirdownward movements and by the striking of the type against the platen.Moreover, the structure affects only the connection between the link 8and the rock-shaft, and said connection may be readily applied tomachines already built.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a type-writing machine, the combi nation with a movable type-head,of actuating means therefor including a rock-shaft, a crankarm capableof relative movement with respect to the shaft, alongitudinally-unyielding connection between the crank-arm and head,

and; a yielding connection between the shaft and crank-arm.

2. In a type-writing machine, the combination with a movable type-head,of means for operating the head including a rock-shaft, and a connectionbetween the rock-shaft and typehead including a crank-arm looselymounted on the rock-shaft, and a yielding connection between thecrank-arm and shaft.

on the rock-shaft. and a spring coiled upon the shaft, one end of saidspring being attached to the arm, the other end being connected to theshaft.

4. In a type-writing machine, the combination with a pivoted type-bar,of operating mechanism therefor including a rock-shaft, a crank-armloosely journaled on the rock-sh aft, a yielding connection between thecrank-arm and shaft, and a rod connecting the cr ank-arm and type-bar.

5. In a type-writing machine, the combination with a movable type-head,of means for operating the head including a rock-shaft, and alongitudinally-unyielding connection between the rock-shaft andtype-head including a crank-arm, and a yielding connection between theerank-arm and shaft.

6. In a type-writing machine, the combination with a movable type-head,of a rockshaft, a'crank-arm having a connection with the type-head, ayielding connection between the shaft and the crank-arm, and a stop forlimiting the yielding movement of the connection.

7. In a type-writing machine, the combination with a movable type-head,of a rockshaft, a crank-arm loosely journaled on the shaft and having aconnection with the typehead, a spring connection between the shaft andcrank-arm, and a stop carried by the shaft and located in the path ofmovement of a portion of the crank-arm.

8. In a type-writing machine, the combination with a pivoted type-bar,of a rock-shaft, a crank-arm having a hub loosely mounted on the shaft,a link connection between the typebar and crank-arm, a spring connectionbetween the crank-arm and rock-shaft, said hub of the crank-arm having aslot, and a stoppin carried by the rock-shaft and projecting into theslot of the hub.

9. In a type-writing machine, the combination with a movable type-head,of a rockshaft, a device movably mounted on the rockshaft and having alongitudinally-unyielding connection with the head, and a yieldingconnection between the shaft and device.

10. In a type-writing machine, the combination with a pivoted typebar,ofa rock-shaft, a crank-arm, a rod connecting the type-bar and crank-arm,a spring coiled upon the rockshaft and connected with the crank-arm, andmeans for varying the tension of the spring.

11. In a type-writing machine, the combination with a pivoted typebar,ofa rock-shaft, acrank-arm loosely journaled on the rock-shaft and havinga connection with the type-bar, a

spring coiledupon the rock-shaft and having a connection at one end withthe crank-arm, a collar mounted upon the rock-shaft and hav ing aconnection with the other end of the spring, and a set-screw for holdingthe collar against movement and in position upon the rook-shaft.

In testimony that I claim the foregoing as my own lhave hereto aflixedmy signature in the presence of two witnesses.

WALTER JEROME CAMPBELL.

Witnesses:

G. D. CRAIG, M. E. HILL.

